In wireless networks a time variant channel may cause fluctuations in communication link qualities. A receiver may compute the channel qualities and feed-back information to a transmitter. This feedback may assist the transmitter in selection of modulation and coding schemes (MCSs) for the link. For a multiple-input, multiple-output (MIMO) link, the number of spatial channels (or “layers”) may also be adapted to the channel qualities. The total number of active spatial channels may be referred to as the rank. Adapting the MCS and rank in light of channel conditions may be referred to as link adaptation.